This invention relates in general to corner joint constructions and in particular to a new and useful corner joint of a mitered jamb of a door frame in which the individual elements forming a corner include claws which interengage.
In a prior art corner joint of this kind, disengageable claw locks are provided, with the claws for engaging the upper horizontal door frame member projecting into the miter region from clamping plates which are provided on the two vertical jambs of the frame. The interengageable claws push the frame parts apart.
To obtain an additional connection, some snap elements are secured to the backside of the U-section frame. A relatively large number of individual parts is thus needed for the connections (German OS No. 21 07 273).
In another prior art corner joint, the frame jambs are provided on their outside with spring legs projecting into the miter region. These spring legs are designed as semicircular engaging heads which are bent toward the inside of the jamb close behind the jamb end of the respective frame jamb. The engaging head is followed by an outwardly extending portion having an engaging cam and a cross web. The spring legs are provided on the jamb ends in mutually offset positions and their dimensions are such that engaging cams of one of the spring legs engage behind the cross web of the other spring leg (German OS No. 27 01 208). This connection again requires individual parts.
Either of these prior art claws and engaging locks has the particular disadvantage that the individual connecting elements must be separately manufactured and then welded to the frame jambs in exact aligned positions. This is expensive.